The Acoustical Society of AmericaThe newsletter of

Some 40 years ago an acoustics major was established inthe Escuela Superior de Ingeniería Mecánica y Electrica(ESIME) at the National Polytechnic Institute in Mexico Citywith 9 different acoustics topics, including fundamentals, trans-ducers, audio, architectural acoustics, music, noise and vibra-tion, speech recognition, bioacoustics and electro-medicalequipment, and acoustics metrology in the program.Universidad Nacional Autónoma de México (UNAM), the larg-er and older university in Mexico, with the largest acoustics lab-oratory in Mexico City that includes anechoic and reverberantchambers, offers a masters degree in acoustics, and research isconducted in physical acoustics, measurements and transducers,vibration and architectural acoustics in other facilities of the uni-versity in Mexico City and Cuernavaca. Centro Nacional deMetrología (CENAM), the national metrology center (equiva-lent to NIST) includes primary calibration acoustics and vibra-tions laboratories in the State of Queretaro, and maintains rela-tionships with NIST, PTB, etc. Universidad Autónoma deNuevo León (UANL) in Monterrey, in northern Mexico dealswith noise and vibration, audio, architectural acoustics andmeasurements; the University of Guadalajara, Jalisco, in thewest, has been working for many years in environmental noise,and is now involved in Mexico’s largest study of noise in cities.Many other universities and technological institutions aroundthe country have been working on vibrations, measurements,audio, speech communications, audiology, noise, speech, under-water acoustics, agricultural applications and bioengineering,among other topics. The number of students and researchersinterested in acoustic topics such architectural acoustics, music,biological acoustics, psychological acoustics, speech communi-cation, and archaeological acoustics is increasing.

Several technical societies and professional colleges dealwith acoustic matters within the country and include acousticssessions in their annual or bi-annual meetings, and some areaffiliated to their counterparts mainly in the United States: theMexican Institute of Acoustics IMA, with the AcousticalSociety of America ASA, I-INCE, FIA, ICA, and IIAV; AESMexico, with the Audio Engineering Society; the MexicanAssociation of Broadcast Engineers and Technicians (AMI-

Volume 20, Number 4Fall 2010

TRA) with the Society of Broadcast Engineers (SBE); theAcademy of Engineering; and the Electronics andCommunications Engineers College, which has a program tosupport Acoustics Experts.

Major research centers working in noise, vibration andother acoustics matters include the Mexican Institute ofTransportation (IMT); the Queretaro Technical Research Center(CIATEQ); violin research at the Lauderia center handled by theFine Arts National Institute (INBA) in Queretaro; BiologicalResearch Center (CIBNOR), La Paz, Baja California; theInstitute for Electrical Research Center (IIE), in Palmira,Morelos; Center for Nuclear Research (ININ) in Salazar, Estadode Mexico; the Test, Equipment and Materials Laboratory(LAPEM), Irapuato, Guanajuato; Research and AdvancedStudies Center (CINVESTAV), with several installations in dif-ferent cities; and the Mexican Oil Institute (IMP) in Mexico City.

With regard to standardization, Mexico began to developaudio standards in the 1950’s, and sound, noise and vibrationstandards in the 1970’s, related to environmental and industri-al noise and vibrations, noise generation by new vehicles(pass-by), and exhaust noise, architectural acoustics and soundmeasurement procedures, many of them equal or similar to the

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Acoustics in MexicoSergio Beristain

Fine Arts Palace, showing the crystal curtain with the snowyPopocatepetl and Istacihuatl volcanoes

Newsletter of the Acoustical Society of AmericaProvided as a benefit of membership to ASA members

The Acoustical Society of America was organized in 1929to increase and diffuse the knowledge of acoustics and topromote its practical applications.Echoes Editor . . . . . . . . . . . . . . . . . . . . .Thomas RossingASA Editor-in-Chief . . . . . . . . . . . . . . . . . . . .Allan PierceAdvisors . . . . . . . . . . . . . .Elaine Moran, Charles Schmid

Phone inquiries: 516-576-2360. Contributions, includingLetters to the Editor, should be sent to Thomas Rossing,Stanford University, CCRMA Department of Music,Stanford, CA 94305 <rossing@ccrma.stanford.edu>

We hear that . . .

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� ASA and the Optical Society ofAmerica (OSA) have announced 4 neweducational posters in their “MakeWaves—Discover Science” posterseries, including one on acoustics andone on echolocation created jointly withASA. The posters are available inEnglish, Spanish, French, Russian, andMandarin. Posters can be requestedfrom opticseducation@osa.org.� The 2010/2011 AIP/ASA CongressionalScience and Engineer-ing Fellowship wasawarded to PeterNorgaard, a physicistat Princeton University.Only one out of 50applicants for theFellowship was a member of ASA.� The former Technical Committee on

Biomedical Ultrasound/Bioresponse to Vibration haschanged its name to Committee on Biomedical Acoustics.� ASA will co-sponsor meetings on AcousticCommunication by Animals (Cornell University, August2011), Aging and Speech Communication (IndianaUniversity, October 2011), and Fish Population Estimation(Seattle, May 2011).

Peter Norgaard

Letter from the EditorOne of the joys of my life is meeting old friends and

making new friends at acoustics meetings. I have justreturned from two international acoustics meetings inAustralia, the International Congress on Acoustics (ICA) inSydney and an International Symposium on MusicalAcoustics (ISMA2010) in Sydney and Katoomba. A reporton the ICA by Charles Schmid, who is now vice-president ofthe International Commission for Acoustics, appears else-

where in this issue. Considering the distance to Australia,ASA was well represented at ICA, and we were especial-ly proud of the fine lecture by Leo Beranek who receiveda special award from the Australian Acoustical Society.

It was my first visit to Australia in 30 years, since Itaught at the University of New England in Armidale. Afterthe ICA. I participated in a satellite conference on musicalacoustics (ISMA2010) which began in Sydney and contin-ured in Katoomba in the scenic Blue Mountains. A satelliteconference on Architectural Acoustics took place inMelbourne. These smaller conferences provide ideal set-tings for informal discussions with acousticians having sim-ilar interests. Our ISMA included some enjoyable hikesorganized by Joe Wolfe and John Smith and colleagues atthe University of New South Wales.

While this issue of ECHOES is being printed, I will beon my way to Vienna Talk 2010, an international symposiumcelebrating the 30th anniversary of the Institute of MusicalAcoustics (Wiener Klangstil) of the University of Music andPerforming Arts. “Wien, Wien, nur du allein” is the refrainof a well-known song about “Vienna, City of my Dreams.”

Joe Wolfe demonstrates a simulated didgeridoo to Tom Rossing.(photo by C. Schmid)

Sophie and Antoine Chaigne in the Blue Mountains duringISMA. (TR)

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Acoustics in Mexicocontinued from page 1International Standardization Organization (ISO) standards,with minor updating and a few new ones from 1994 to date;many of these standards can be obtained at the CommerceMinistry web-page. Now it has two major divisions NOM stan-dards which are compulsory (the mentioned noise and vibra-tions related standards are NOM), and NMX standards, thatwork as recommendations. Recently an updating and new stan-dards program is being carried out by the Mexican Institute ofStandardization and Certification (IMNC) affiliated with ISO.

Among the most important acoustics recreational and cul-tural installations around the country are found many closedand open theaters, auditoria, TV, broadcast, and recording stu-dios, such as Theatre Juarez, Theatre Degollado, the CulturalCenter Ollin Yolitzly, Nezahualcoyotl Concert Hall, the FineArts Palace, the National Arts Centre, the largest circularrecording studio, pyramids and basements, several large audito-riums, etc. Some of them were designed by foreign acousticiansand others were designed by Mexican acousticians, who alsohave designed office and apartment buildings, movie theaters,

school and industrial laboratories, etc. Archaeologists have alsofound thousands of sound sources, such as noise generators,flutes, ocarinas, and many other pre-Columbian sound andmusical instruments, and some of them have been studied indetail by Mexican researchers.

Mexico is hosting the 2nd Pan-American/Iberian Meetingon Acoustics that will be held in Cancun, QR, in 2010 withmore than 90 special technical sessions, so Mexicans have theirarms wide open in order to receive over a thousand foreignattendees to share experiences.

Sergio Beristain, Inst. Mexicano deAcustica, is president of the AcousticalSociety of Mexico and co-chairman of the2nd Pan-American/Iberian Meeting onAcoustics in Cancun. He is a Fellow ofASA, a member of the TechnicalCommittee on Architectural Acoustics,and researcher on noise and vibration.

Samir N. Y. Gerges

The Ibero-American Federation of Acoustics (FederacionIberoamericana de Acustica – FIA) is a non-profit scientificassociation, created in October 1995, in Valdivia, Chile. Itsmembers are the acoustical societies of the Spanish andPortuguese speaking countries (Argentina, Brazil, Chile, Peru,Colombia, Mexico, Venezuela, Portugal and Spain) withUruguay as an observer member.

The acoustical societies of South America have beenworking together, mainly organizing conferences such as the1st Brazilian-Argentine Acoustics Congress (I CongresoBrasileño-Argentino de Acústica), that took place inFlorianópolis, in April 1994, and several other congressesorganized by the Valdivia Austral University AcousticsInstitute (Instituto Acústico de la Universidad Austral deValdivia, Chile) in 1994 and 1995, also with the participationof the acoustics societies of Spain, Peru, and Argentina. FIAcongresses have taken place in Florianopolis, Brazil (1998),Madrid, Spain (2000), Cancun, Mexico (2002 and 2010),Guimarães, Portugal (2004), Santiago, Chile (2006), andBuenos Aires, Argentina (2008).

The aim of the Ibero-American Federation of Acoustics isthe development of acoustics science and technology areas,gathering the Spanish and Portuguese speaking countries asso-ciations; its main goals are:

• To invite the associations working in the field ofacoustics to become members of the Federation, in order topromote its development.

• To establish links between acoustics associations, privateand public companies, scientific institutes and universities,

syndicates, etc. • To contribute and promote the creation of new Acoustic

Associations in Ibero-american countries, where they do notexist, and to help and support the existing ones.

• To maintain a broadcasting and information system inacoustics throughout member countries.

• To promote research in acoustics, and the use of the corre-spondent technologies.

• To organize congresses, workshops, courses and meetings,and all activities towards acoustics development.

• To draw cooperation agreements with international organ-izations for the fulfillment of the Federation objectives.

• To promote the exchange of knowledge, experience andinitiatives in each country, acoustics development.

• To push acoustics studies, actions and planning, at all lev-els, and at both technical and university levels.

• To promote the production of standards and recommenda-tions on environmental acoustics to improve the quality of life.The FIA is an affiliated member of the International Commissionfor Acoustics (ICA) and an observer member of the InternationalInstitute of Noise Control Engineering (IINCE) and InternationalInstitute of Acoustic and Vibration (IIAV).

Samir N. Y. Gerges, Vice-president of FIA,is in the Laboratory of Acoustics andVibration in the Mechanical EngineeringDepartment of the Federal University ofSanta Catarina in Brazil. He is a Fellow ofASA and president of ICA.

ASA returns to Cancun

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The 2nd Pan-American/Iberian Meeting on Acoustics inCancun, Mexico November 15-19 will be a gala internationalaffair which combines the 160th meeting of ASA with the 7thIberoamerican Congress on Acoustics and the 17th MexicanCongress on Acoustics. Certainly everyone who participated inthe 1st meeting in Cancun in 2002 will want to be a part of thismeeting as well. The co-chairs, including James West, SamirGerges, and Sergio Beristain, who handled the 1st meeting sowell, are serving again. Mark Hamilton is the technical programChair, Charles Schmid is vice chair, and Rebeca de la Fuentewill organize the cultural program.

Cancun has a tropical cli-mate with an annual mean tem-perature of 27 oC (80 F) (averagehigh and low temperatures dur-ing November are 30 and 23 oCand average rainfall is 132 mm).The beaches are spectacular, andit lies near the world’s second

largest coral reef. Some small vestiges of the pre-ColumbianMayan civilization are within Cancun, while great Mayan citiessuch as Chichen-Itza, Uxmal, Coba, and Tulum are nearby. Someof the world’s best snorkeling sites are easily accessible.

The technical program will feature more than 900 invit-ed and contributed papers organized into 93 sessions. A “hottopics” session will cover new developments in architectural

acoustics, animal bioacoustics, and engineering acoustics. Atutorial on “Forensic Voice Comparison and ForensicAcoustics” will be given on Monday, 15 November byGeoffrey Stewart Morrison (University of New South Wales)and Daniel Ramos (Autonomous University of Madrid). Theregistration fee of $15 until October 5 and $25 at the meeting,($7/$12 for students) includes a set of notes.

An instrument and equipmentexhibit is scheduled for the FiestaAmericana Grand Coral BeachHotel Monday through Wednesday.Technical committees will hold openmeetings on Tuesday, Wednesday,and Thursday evenings. Buffetsocials with cash bar will be held onTuesday and Thursday evenings. Aguitar concert featuring famousMexican guitarist Juan Carlos Laguna will take place onThursday afternoon at 5:00 p.m. following the special sessionon guitar acoustics. The Women in Acoustics luncheon willbe held on Wednesday, 17 November, as will the Plenary andAwards session.

There will be a post meeting tour to historic Uxmal, MeridaCity and Chichen-Itza leaving Saturday, 20 November, at 8:00am and returning Sunday at 9:00 p.m. Further details can befound at http://acustica-cancun.blogspot.com.

Technical program committee meeting. Front Row (L to R):Fernando Elizondo, Sergio Beristain, Judy Dubno, Mark Hamilton, JudyCottingham, James Cottingham, Catherine Rogers Lee, Natalia Sidorovskaia; Back Row (L to R): Michael Scanlon, Charles Schmid, Siu KitLau, Nicholas Chotiros, Kevin Heaney, Angelo Campanella, Christopher Rooke, Jeffrey Ketterling, Thomas Matula, Joel Mobley, PhilipRobinson, Anthony Lyons

Chichen-Itza Uxmal Tulum Fiesta Americana GrandCoral Beach Hotel

Snorkeling in Cancun

Juan Carlos Laguna

ECHOES from ICA

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The 20th International Congress onAcoustics (ICA) was held in Sydney,Australia from August 23rd to August 27th.There were over 1,000 registrants represent-ing 38 countries. The largest representationcame from Japan (25%) and Australia(18%), followed by the United States, Korea,and China, with 6% each. The main organ-izers were Marion Burgess (Chair), DavidAnderson (Secretary) and Chris Schulten(Treasurer).

The opening ceremonyfeatured a blessing by an aboriginalspokesman accompanied by fouraboriginal dancers and the playingof a didgeridoo.

Over 900 papers were pre-sented at the Sydney ConventionCenter situated on DarlingHarbor. The five plenary speakersincluded Australians GraemeClark, who spoke on cochlearimplant speech perception, andJoe Wolfe whose talk was on the acoustics of wind instru-ments. Torsten Dau from the Technical University ofDenmark, presented a distinguished lecture on human audi-tory processing in complex acoustic environments. He was

the recipient of the 2010 InternationalCommission for Acoustics EarlyCareer Award. Among the eight dis-tinguished and special lecturers wasLeo Beranek who received both theInternational Commission for Acous-tics lifetime achievement award andan honorary fellowship from theAustralian Acoustical Society.

ICA meetings are held everythree years. The 21st ICA will be heldin Montreal Canada, June 2–7, 2013.

It will be a joint meeting with the Acoustical Society ofAmerica and the Canadian Acoustical Association with

20th ICA in SydneyCharles E. Schmid

Michael Stinson serving as Chair. Following tradition, theorganizers of ICA 2013 provided a drink–ice apple wine fromMontreal–for the farewell reception. The InternationalCommission for Acoustics voted to hold the 22nd ICA meet-ing in Buenos Aires, Argentina in 2016. The followingacousticians were elected officers at the General Assemblyheld on August 24th: Michael Vorländer, president; CharlesSchmid, vice-president; Samir Gerges, past-president;Marion Burgess, secretary general; and Antonio Perez Lopez,treasurer. Hugo Fastl was congratulated for his work as out-going treasurer and Sonoko Kuwano for her contributions asoutgoing vice president.

Funds from the International Commission for Acousticsand the Acoustical Society of America provided support for theYoung Scientists Awards. These awards allowed 29 studentsfrom around the world to attend and exchange information withother acousticians, many of whom the students would typicallynot have the opportunity to meet in person.

Satellite meetings included the International Symposium onRoom Acoustics (Melbourne), International Symposium onMusical Acoustics (Blue Mountains and Sydney) and theInternational Symposium on Sustainability in Acoustics(Auckland, New Zealand).

The ICA 2010 Organizing Committee is to be congratu-lated for choosing a beautiful city with its famous operahouse, and for bringing together so many interesting speakersfrom around the world. Additional information on theInternational Commission for Acoustics can be found atwww.icacommission.org.

Didgeridoo opens the ICA (photo byGlen Slough)

International Commission for Acoustics officers (l to r): Hugo Fastl (pasttreasurer), Sonoko Kuwano (past vice-president), Michael Vorländer(president), Charles Schmid (vice-president), Samir Gerges (past presi-dent), Marion Burgess (secretary general) (photo by C. Schmid)

ICA's Lifetime Achievementaward presented to LeoBeranek by Samir Gerges

ICA Meeting ChairsMike Stinson andMarion Burgess(photo by C. Schmid)

Scanning the journalsThomas D. Rossing

� The sound from striking a basketball is found to have over 50partials in the frequency range of 0-12 kHz according to a paperin the June issue of American Journal of Physics.The frequencies closely match those expected for a sphericalacoustical cavity of basketball size. The lowest observed

mode frequency is more than an octave lower than the firstspherically symmetric mode, as predicted by Rayleigh.� The July/August issue of Smithsonian celebrates its 40thanniversary by asking 40 prominent Americans to write briefessays about breakthroughs, trends, and events likely to

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Scanning the journals

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shape our world over the next 40 years. President Obama isoptimistic that “the nation will meet the tests and seize theopportunities of the century ahead.” A poll conducted by thePew Research Center and Smithsonian found optimism aboutscience and social progress despite worries about the environ-ment and population growth. Composer Tod Machover predictsthat composers will no longer be the only people capable ofcomposing music, while musician and writer Laurie Andersonpredicts that “sound systems that replicate how we hear willreplace the stereo.”� An atomic force microscopy (AFM) method for assessingelastic and viscous properties of soft samples at acoustic fre-quencies under non-contact conditions is described in the 20June (online) issue of Nature Methods. The technique, which isbased on hydrodynamics theory of thin gaps, has enabled thestudy of the microrheology of biological tissues that produce ordetect sound such as the tectorial membrane of a guinea pig.� The acoustics of biphonic and monophonic birdsongs aredescribed in an interesting paper in the August issue ofAcoustics Australia. Some birds produce songs with individualnotes or “syllables” that may be almost pure tones or may havea rich spectrum of harmonics. Those species known as song-birds, which are able to sing two different notes at the sametime, have two bronchial valves in their syrinx. The calls ofsome birds such as cockatoos, have a truly chaotic waveformrather than simply a broad spectrum. Collaborative studiesbetween many biological and physical scientists have nowachieved a basic understanding of birdsongs, but there is animmense field of research available on the information contentand cultural background as well as on the vocal anatomy andphysiology of individual bird species.� Although police departments spend thousands of dollars onvoice stress analyzers, scientists question voice-based liedetection, according to an article in the July 3 issue of ScienceNews. Airports are considering versions for security screeningand insurance companies may employ them to detect fraud, butthese tools have a poor track record in actually telling truth fromdeception. Speech does change, both in frequency and in theamount of time spent on segments or words, when a person isunder stress, but distinguishing stress related speech to decep-tion from stress related to fatigue, anxiety or fear is not easy.� Whales may compensate for increased ocean noise byincreasing amplitude when they call to one another in thecoastal waters of the eastern United States and Canada withhigh levels of commercial, naval, and recreational shipping traf-fic. Whales were found to use a tactic similar to what humansuse in communication in a noisy bar. Sound is an importantaspect of their survival because they rely on it for vital life func-tions, such as communication, navigation and feeding. Unlikeland animals, sea creatures can find it difficult to escape areasof loud ambient noise, the researchers point out.� Analyzing the pressure data in a spark ignition engine duringcombustion shows that the level of noise increases considerablydue to nonlinear dynamics in the combustion process, accord-

ing to a brief in the April/May issue of The Industrial Physicist.� Feedback effects that lead to strong coupling between sin-gle electron transport and mechanical motion in carbon nan-otube nanomechanical resonators is discussed in a letter in the1 July issue of Nature. Noise measurements show that mesoc-scopic back-action of electrons tunnelling through a quantumpoint contract causes driven vibrations of the host crystal. � An experiment using 40-kHz ultrasound to verify Babinet’sprinciple is reported in the July issue of American Journal ofPhysics. Babinet’s principle predicts that the sum of diffractionfields behind complementary objects (an aperture and a disk ofthe same size and shape) is the same as the field would be with-out the two objects. Verification of Babinet’s principle is gen-erally done using visible light in the Fraunhofer regime wherethe source and the observation planes are far from the diffract-ing objects. Given the relatively long wavelength of the ultra-sound, however, it was possible to verify Babinet’s principle inthe Fresnel regime in which the source and observation planesare close to the diffracting objects.� Efforts by the National Academy of Sciences to popularizescience through movies may sanitize it as well, a writer in the1 July issue of Nature worries. The Science and EntertainmentExchange of the US National Academy of Sciences, whichstarted in 2008, links scientists and engineers with movie andtelevision show makers to provide “the credibility andverisimilitude on which quality entertainment depends.” Theexchange aims to increase public appreciation and support forscience and to counter antiscientific sentiments through accu-rate and positive portrayals of science, but the author sees dan-ger in efforts to render science and scientists more familiar andpalatable through mass entertainment.� A paper in the May issue of Acoustical Science and Technologydeals with the influence of short-term meteorological variationson noise prediction. Both acoustical and meteorological meas-urements were made simultaneously over 10-minute periods, andpredictions based on the parabolic equation method agreed wellwith measurements around sunrise and sunset.� Ultrafast laser pulses (“nanoshocks”) are being used to studyshock behavior in tiny samples such as thin films, accordingto a paper in the July 15 issue of Journal of Applied Physics.Materials are shocked at high pressure in a diamond anvil cell.The time scale is short enough to permit direct comparison withmolecular dynamics simulations which usually run for less thana nanosecond.� An ultrafast blue-violet (405 nm) semiconductor laserwith 100-W output could make possible Blu-ray discs capableof storing 1 TB of data, according to a report in the July 21 issueof Applied Physics Letters. This is about 20 times more infor-mation than Blu-ray discs currently hold. The laser is capable ofgenerating pulses 3 picoseconds long with a repetition rate of1 GHz.� In order to recognize the source of a sound we first have tolearn its acoustic characteristics. According to a paper in the 27May issue of Neuron, such learning is subconscious, rapid, andremarkably robust. When subjects listened to a series of short

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Scanning the journals

snatches of random noise and to identify which snatches includ-ed repetitions, their success rate was below 50%, but when onespecific snatch was secretly and randomly interspersed at fre-quent intervals, the listeners quickly became near perfect indetecting repetition even when the snatch was compressed intime or reversed. Moreover they retained the memory for sev-eral weeks.� Teachers who include a general discussion of wave motion intheir introduction to acoustics will find a paper on demon-strating surface gravity waves in a fish tank in the May issueof the American Journal of Physics useful. The speed of surfacegravity waves (ocean waves, for example) varies with depth aswell as with wavelength.� An anthropologist at the National Museum of Natural Historyhas made 3-dimensional scans of several old violins byStradivari and others and reports some of his findings in theMay issue of Smithsonian. One distinguishing characteristic ofa Stradivarius is thinner body plates� Bats and humans have some of the best hearing in the animalkingdom, thanks to a snail-shaped coiling of the cochlea. Apaper in the 5 August issue of Proceedings of Royal Society Bsheds light on how this evolved by describing a 150-year oldfossil of a mammal having a bony inner ear that is curved rather

than coiled. It is suggested that the cochlea was innervatedbefore it attained its present shape.� The proceedings of the Interactive Sonification workshop -ISon 2010, held in Stockholm in April, are now available on-line at http://www.interactive-sonification.org/ISon2010/ pro-ceedings/ The proceedings are licensed as an Open Access pub-lication.� Geophysicists used audio recordings along with time-lapseimagery and seismic recordings to study iceberg calving in out-let glaciers around Greenland, according to a paper in theJournal of Geophysical Research 115, 2010. In particular theinteraction between the glacier and its proglacial ice melangewas studied. Sea ice growth in winter stiffens the melange, ulti-mately preventing calving of full thickness icebergs, but in sum-mer the melange weakens and the terminus retreats. � Music engages more of the brain than any other stimulus weknow, according to an article in the August 14 issue of ScienceNews. This article is part of a special section on Mind andMusic. Although neuroscientists have largely dismissed the“Mozart effect” as myth, practicing and performing music doesseem to elevate certain cognitive capabilities, and music therapyappears to help alleviate several brain maladies. From their veryfirst days, babies use a musical sense to exchange emotional ban-ter with their mothers, perhaps priming them to learn language.

Acoustics in the News� Noise from ships can double the noise levels in some partsof the ocean, swamping the low-frequency wavelengths thatwhales use to communicate and navigate their watery world,according to a story in the 18 June issue of Science. Althoughsonar and air guns have grabbed headlines, acoustic clutter cre-ated by nearly 100,000 large commercial ships is arguably thesea’s most pressing sound problem. Over the past 50 years, thegrowing trade fleet has contributed to a 32-fold increase inlow-frequency noise in some parts of the ocean. Leaders in theInternational Maritime Organization, a United Nations groupthat oversees shipping, has been called on to explore technicaloptions for quieting ships. Changing propeller design to reducecavitation is considered one of them. Other gains could comefrom mounting noisy engines on sound-insulating platformsand streamlining boxy hulls.� According to a story in the May 31 issue of the San JoseMercury News, Willy Moss and Mike King at the LawrenceLivermore National Lab and Eric Blackman at the Universityof Rochester have done research on traumatic brain injuries(TBI) in soldiers that should lead to better combat helmets (seeScanning the Journals in the Winter 2010 issue of ECHOES).Blasts from improvised explosive devices and other bombsmay penetrate the brain by squeezing the skull, causing tinyripples that trigger a cascade of reverberating waves.Traditional helmets have emphasized protection from flyingfragments and impacts but not blasts.� The age of the silent hybrid automobile may be coming to anend, according to an Associated Press story on July 5 which

appeared in several daily newspapers. Some researchers andsafety groups say that quiet operation can pose risks for unsus-pecting pedestrians and especially the blind who rely on soundcues. Congress is adding sound-performance requirements forhybrids and electric cars to an auto safety bill under consider-ation. Some automobile manufacturers are considering vari-ous warning devices including a sound that changes pitch asthe car accelerates. � Although scientists have been working on both fingerprintsand voiceprint recognition for some time, a direct comparisonhas yet to be made, according to a story in the May 18 issue ofThe New York Times. Fingerprint identification is based onstandard images and standard features from visual samples,while voice identification converts sound signals into a digitalstream of samples. Voice-based security systems usually relyon matching a set of prerecorded words, which is not practicalin analyzing a wiretapped conversation. (See story on voice-based lie detection in “Scanning the Journals.)� “We as a scientific community have made inadequate use ofthe Internet to tell everybody what we do, to exchange infor-mation among ourselves, to bring the results of publicly sup-ported science to the attention of everybody,” Nobel laureateHarold Varmus charged in a recent interview, according to July3 issue of Science News. Although groups that are doing fron-tier science may be relatively small, there are a lot of peoplewho have a big interest including teachers, journalists, andpeople in the health service professions, he pointed out.

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Acoustics in the News

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� Although the FIFA, the world soccer body, regards vuvuze-las as an icon of South African culture and has refused to banthem, TV broadcasters have developed audio filters to cutdown on their whining rasp according to a story in the June 16issue of The New York Times. Sports fans at the stadiums havebeen rediscovering the usefulness of the humble ear plug.� An unusual feature of the new Shalin Liu PerformanceCenter in Rockport, Massachusetts is the two-story glass win-dow at the rear of stage that can be left open to view the har-bor or covered by wooden screens giving what some listenersdescribe as a “slightly warmer sound.” The reviewer in theJune 14 issue of The New York Times liked the small (330-seat)hall, the new home of the Rockport Chamber Music Festival.� Sonification of data from the Atlas detector may give physi-cists at the Large Hadron Collider (LHC) another way to ana-lyze their data, according to a story in the June 22 issue of BBCNews (online). A close event will generate a low pitch, a moredistant event a higher pitch. A higher energy will generate alouder sound. The sonification team believes that ears are bet-ter suited than eyes to pick out the subtle changes that mightindicate the detection of a new particle.� After a concert violinist played on the famous 269-year oldVieuxtemps violin by Guareneri del Gesù, a small group of sci-entists, engineers, and violin makers made careful measure-ments on this and three other valuable old violins, according toa news focus in the 18 June issue of Science. The instrument,priced at $18 million, was played and examined along withother 18th century violins made by Stradivari, and Guadagnini.The violins spoke with voices as distinct as people’s but it isdifficult to distinguish them by scientific tests such as modalanalysis, sound spectrum analysis, or CT scans, or even by lis-tening to their sounds as played by skilled violinists.

Sound spectra and other frequency response functions of

fine violins show many peaks or resonances distributedthroughout the playing spectrum, and some are consideredmore important than others. Around 280 Hz is the importantA0 mode in which sound is radiated through the f-holes.Around 480-550 Hz are prominent resonances that give a “full-ness” of sound and around 3000-3500 Hz is a collection of res-onances (sometimes called the “bridge hill”), not unlike the“singer’s formant” characteristic of good opera singers. CTscans show evidence of past repairs made to most violins tomaintain quality, but the scans show the Vieuxtemps to be pris-tine, which may mean its sound has changed less through theages.� Sound absorbing asphalt being used in repaving someCalifornia freeways highway noise by as much as 6 dB, com-pared to dense asphalt, according to a story in the July 20 issueof the San Jose Mercury News. The new asphalt, developed atthe University of California, is applied in three layers, the toplayer of whch is open-graded asphalt with sound-absorbing airpockets. It is backed by a layer of rubberized asphalt to pro-vide durability. Other states, such as Washington and Oregon,are also using open-graded asphalt for sound reduction as wellas skid resistance.� Data tapes made by astrophysicist James Van Allen in the1950s when he discovered the “Van Allen belts” are character-ized as “music to his ears” in a note in the 18 June issue ofScience. The scientists learned to identify “melodies” withcadenzas warning of potential hazards to human space travel.The tones on the tapes indicated the intensity of cosmic rays,and the static was eventually interpreted as being from radia-tion belts—zones of high-energy protons and electrons that thesatellites passed through in their orbits. The tapes have startedto show signs of mold, so the library and physics departmentsat the University of Iowa have joined forces to preserve thearchive and digitize the tapes for posting on the Internet.

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